If you can’t hash out the idea then so you have a right to even try and make a game?
This is the most important thing I see here, because the answer is always ‘yes’. Of course you have the right. Start where you’re at and figure out what you need as you go along. Your first attempt might not work, but what you learn from it will be invaluable.
As far as art goes, you can either find someone who is excited to work on it with you in their spare time (difficult to find), or pay an artist whose style you like to create art for you (possibly expensive). If you do the latter, it’s best to wait until you have a clear idea of what you’ll need so you don’t end up paying for assets you won’t use.
One thing you can do right now is create a design document. This is basically just a long, detailed description of what you would like your game to be: specific mechanics and systems you want to include, what the gameplay loop will be, the audiovisual style, everything. Include images mood-board style for your future artist(s). This document will give you an idea of the assets you’ll need, as well as what you’ll need to learn as far as coding. It doesn’t have to be followed to the letter, but it’s a good place to start.
My partial degree in Game Art and Design finally pays off, lol